Development and Preliminary Validity Evaluation of Numerical Simulation of Human Swallowing Using a Particle Method

This study evaluated the possibility of numerically simulation of swallowing via moving particle simulation (MPS), defining the bolus structure as the number of particles. To verify the accuracy of the simulation, a simplified bolus falling model was studied via three-dimensional (3D) MPS. Further, we examined a simplified swallowing simulation via two-dimensional (2D) MPS to verify interactions between food properties and organ structure movement. On comparing the 3D MPS simulation and experimental results, we found that the falling time of the water bolus and configuration of the liquid-air interface corresponded to the experimental measurements and visualization images, respectively. Moreover, the calculated force on the surface was similar to the theoretical and measured values with adequate rheological and tribological properties. In the simplified 2D MPS swallowing simulation results, the food bolus exhibited different flow behaviors and deformations, thus confirming that MPS can be used for coupled simulations of food and organ structures with differing physical properties. The results suggest that MPS can be used to develop a numerical simulation of the swallowing process.